Hi,recently I discovered an amazing effect at a water outlet of the denitrator at my freshwater breeding tanks.During a routine check at night I saw thousand of tiny air bubbles bustling and floating below the outlet. The size of the bubbles were actually even much smaller than commonly known from marine tank skimmers.

With most of the tiny air bubbles dissolving before reaching the water surface, the simple setup could probably make a good replacement of traditional water aeration, even for densely populated freshwater tanks. To the extent of full oxygen saturation at all water temperatures.

The filtered water drops (without any pressure !!) through an air control and a short piece of silicone hose. In order to generate the air bubbles, the correct height and frequency must be carefully adjusted. Surely anyone interested could easily rebuild the system.I assume some sort of resonance between drop and water waves creates the steady stream of air bubbles. Does anyone know more about that issue?

During daytime and with naked eyes the effect is almost invisible. But at dark, in the spotlight of a torch, a spectacular bright firework like fountain appears.

A short video clip illustrating the effect I have uploaded to YouTube.

I'd really like to know whether anyone else did reproduce and observe this effect, or even better, was able to improve the setup I had described here. All my tanks are now fitted with those droppers and the inhabitants seem to be quite happy with it.